Captive portal detection

• US 10,491,494 B2
• Filed: 03/06/2018
• Issued: 11/26/2019
• Est. Priority Date: 11/23/2017
• Status: Active Grant

• Current Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Original Assignee: Harman International Industries Incorporated (Samsung Electronics Co. Ltd.)
• Inventors: Shanbhag, Sandeep
• Primary Examiner(s): Zhao, Wei
• Application Number:
  US15/912,853
• Publication Number:
  US 20190158372A1
• Time in Patent Office: 630 Days
• CPC Class Codes: H04L 2101/663 Transport layer addresses, e.g. aspects of transmission control protocol [TCP] or user datagram protocol [UDP] ports
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 61/5038 for local use, e.g. in LAN or USB networks, or in a controller area network [CAN]
• CPC Class Codes: H04L 61/5092 by self-assignment, e.g. picking addresses at random and testing if they are already in use
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04W 12/06 Authentication
• CPC Class Codes: H04W 12/50 Secure pairing of devices
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method for detecting a captive portal on a Wi-Fi network in which a device generates a random private IP address and attempts a TCP connection on HTTP port 80 and HTTP port 8080. Upon an unsuccessful TCP connection a determination is made that no captive portal is associated with the Wi-Fi network and upon a successful TCP connection, a determination is made that a captive portal is associated with the Wi-Fi network.

Claims

1. A method for detecting a captive portal on a Wi-Fi network, the method carried out on a device having a processing unit including a non-transitory computer-readable storage medium configured to execute instructions of a software program, the method comprising the steps of:

connecting to the Wi-Fi network;

acquiring an Internet Protocol (IP) address from a dynamic host configuration protocol on the Wi-Fi network;

setting the acquired IP address as a default gateway to Internet;

generating, at the device, a random private IP address;

attempting a TCP connection to the random private IP address on HTTP port;

80, HTTP port;

8080, or HTTP port;

80 and HTTP port 8080;

upon an unsuccessful TCP connection to the random private IP address, making a determination that a captive portal has not been detected; and

upon a successful TCP connection to the random private IP address, making a determination that a captive portal has been detected.

2. The method as claimed in claim 1 wherein the random private IP address further comprises a random private IP address that is not associated with a subnet of the Wi-Fi network.

3. The method as claimed in claim 1 further comprising the step of notifying a user of the device that the Wi-Fi network has a captive portal.

4. The method as claimed in claim 3 wherein the step of notifying a user of the device further comprises displaying a message at the device indicating that a captive portal exists.

5. The method as claimed in claim 1 wherein the step of making a determination that a captive portal has been detected further comprises step of verifying the captive portal has been detected.

6. The method as claimed in claim 5 wherein the step of verifying the captive portal has been detected further comprises the steps of:

generating, at the device, a plurality of random private IP addresses;

attempting TCP connections to each of the plurality of random private IP addresses on HTTP port;

80, HTTP port;

8080, or HTTP port 80 and HTTP port;

8080;

upon an unsuccessful TCP connection, making a determination that a captive portal has not been detected; and

upon successful TCP connections of each of the plurality of random private IP addresses, making a determination that a captive portal has been detected.

7. The method as claimed in claim 6 wherein the plurality of random private IP addresses further comprises each random private IP address in the plurality of random private IP addresses is not associated with a subset of the Wi-Fi network.

8. A non-transitory computer readable storage medium comprising a program, which, when executed by one or more processors, performs an operation comprising:

connecting a device to a Wi-Fi network;

acquiring, at the device, an Internet Protocol (IP) address from a dynamic host configuration protocol on the Wi-Fi network;

setting the acquired IP address as a default gateway to Internet in a routing table at the device;

generating, at the device, a random private IP address;

attempting a TCP connection from the device to the random private IP address on HTTP port;

80, HTTP port 8080, or HTTP port 80 and HTTP port;

8080;

upon an unsuccessful TCP connection, making a determination that no captive portal is associated with the Wi-Fi network; and

upon a successful TCP connection, making a determination that a captive portal is associated with the Wi-Fi network.

9. The computer readable medium as claimed in claim 8 wherein the step of generating a random private IP address further comprises generating a random private IP address that is not associated with a sublet of the Wi-Fi network.

10. The computer readable medium as claimed in claim 8 further comprising the step of notifying a user of the device that the Wi-Fi network has a captive portal.

11. The computer readable medium as claimed in claim 10 wherein the step of notifying a user of the device further comprises displaying a message at the device indicating that a captive portal exists.

12. The computer readable medium as claimed in claim 8 wherein the step of making a determination that a captive portal is associated with the Wi-Fi network further comprises verifying the determination that a captive portal has been detected.

13. The computer readable medium as claimed in claim 12 wherein the step of verifying the determination that a captive portal has been detected further comprises the steps of:

generating, at the device, a plurality of random private IP addresses;

attempting TCP connections to each of the plurality of random private IP addresses on HTTP port;

80, HTTP port;

8080, or HTTP port;

80 and HTTP port;

8080;

upon an unsuccessful TCP connection, making a determination that no captive portal is associated with the Wi-Fi network; and

upon successful TCP connections of each of the plurality of random private IP addresses, making a determination that a captive portal is associated with the Wi-Fi network.

14. The computer readable medium as claimed in claim 13 wherein the step of generating, at the device, a plurality of random private IP addresses further comprises generating a plurality of random private IP addresses, each of which is not associated with a subnet of the Wi-Fi network.

15. A method for detecting a captive portal on a Wi-Fi network, the method carried out on a head unit of a vehicle, the head unit having a processing unit including a non-transitory computer-readable storage medium configured to execute instructions of a software program, the method comprising the steps of:

connecting the head unit to the Wi-Fi network;

acquiring, at the head unit, an Internet Protocol (IP) address from a dynamic host configuration protocol on the Wi-Fi network;

setting the acquired IP address as a default gateway to Internet on a routing table at the head unit;

generating, at the head unit, a random private IP address;

attempting a TCP connection between the head unit to the random private IP address on HTTP port;

80, HTTP port;

8080, or HTTP port;

80 and HTTP port;

8080;

upon an unsuccessful TCP connection, making a determination that no captive portal is associated with the Wi-Fi network; and

upon a successful TCP connection, making a determination that a captive portal is associated with the Wi-Fi network.

16. The method as claimed in claim 15 wherein the step of generating a random private IP address further comprises generating a random private IP address that is not associated with a subnet of the Wi-Fi network.

17. The method as claimed in claim 15 further comprising the step of notifying a user of the head unit that the Wi-Fi network has a captive portal.

18. The method as claimed in claim 17 wherein the step of notifying a user of the device further comprises displaying a message at the device indicating that a captive portal exists.

19. The, method as claimed in claim 15 further comprises the steps of:

generating, at the head unit, a plurality of random private IP addresses;

attempting TCP connections to each of the random private IP addresses in the plurality of random private IP addresses on port;

80, HTTP port;

8080, or HTTP port;

80 and HTTP port;

8080;

upon an unsuccessful TCP connection, making a determination that no captive portal is associated with the Wi-Fi network;

upon successful TCP connections of each of the plurality of random private IP addresses, verifying the determination that a captive portal is associated with the Wi-Fi network.

20. The method as claimed in claim 19 wherein the step of generating, at the head unit, a plurality of random private IP addresses further comprises generating a plurality of random private IP addresses, each of which is not associated with a subnet of the Wi-Fi network.