Ahmad Alsa'deh

WinSEND: Windows SEcure Neighbor Discovery

Neighbor Discovery Protocol (NDP) is an essential protocol in IPv6 suite, but it is known to be vulnerable to critical attacks. Thus, SEcure Neighbor Discovery (SEND) is proposed to counter NDP security threats. Unfortunately, operating systems lack the sophisticated implementations for SEND. There is limited success with SEND implementation for Linux and BSD, and no implementation for Windows families. Therefore, the majority of the users are not secured with SEND. In this paper, we will introduce an implementation of SEND for Windows families (WinSEND). WinSEND is a user-space application which provides the protection for NDP in Windows. It has direct access to Network Interface Card (NIC) and efficiently handles NDP messages by using Winpcap. WinSEND works as a service with easy user interface to set the security parameters for selected NIC.

Stopping time condition for practical IPv6 Cryptographically Generated Addresses

Cryptographically Generated Addresses (CGA) are employed as an authentication mechanism in IPv6 network to realize the proof of address ownership without relying on any trust authority. The security parameter (Sec) indicates the security level of the CGA address. For Sec value greater than zero, there is no guarantee to stop the brute-force search after certain time. The address generator tries different values of Modifier until (16×Sec)-leftmost-bit of the second hash (Hash2) computes to zero. This paper proposes some modifications to the standard CGA “RFC 3972” in order to limit the time that CGA generation may takes. The modified CGA generation algorithm takes the upper bound of CGA running time as an input and the Sec value is determined as an output of the brute-force computations. The modified CGA keeps track of the best founded Hash2 value during the running time. The paper also proposes to reduce the granularity of the security level from “16” to “8”, to increase the chance to have better Sec value within the time limit. We called the modified CGA as Time-Based CGA (TB-CGA). The implementation and evaluation of TB-CGA are done in this paper.

Multicore-based auto-scaling SEcure Neighbor Discovery for Windows operating systems

SEcure Neighbor Discovery (SEND) is proposed to counter IPv6 Neighbor Discovery Protocol (NDP) security threats. However, SEND is compute-intensive. Fulfilling Hash2 condition in Cryptographically Generated Addresses (CGA) is the main heavy part of SEND. Unfortunately, CGA computation cannot see significant speed improvement when it runs on multicore machine because CGA generation algorithm is sequential. In this paper, we propose a multicore-based high performance SEND implementation for Windows families to speed up SEND computations. The proposed approach automatically detects the number of processors available on a machine and creates equivalent number of working threads to compute Hash2 condition. The parallelization mechanism is implemented to assign CGA computation to all the cores. When one thread satisfies CGA Hash2 condition, the others stop. With the parallel approach, the speedup time has been increased extremely by increasing the number of cores in the computing device. Besides the parallelization, we extend SEND implementation to generate the key pair for CGA algorithm on-the-fly to enhance the security and to protect the privacy.

IPv6 stateless address autoconfiguration: balancing between security, privacy and usability

Included in the IPv6 suite is a method for devices to automatically configure their own addresses in a secure manner. This technique is called Cryptographically Generated Addresses (CGAs). CGA provides the ownership proof necessary for an IPv6 address without relying on any trust authority. However, the CGAs computation is very high, especially for a high security level defined by the security parameter (Sec). Therefore, the high cost of address generation may keep hosts that use a high Sec values from changing their addresses on a frequent basis. This results in hosts still being susceptible to privacy related attacks. This paper proposes modifications to the standard CGA to make it more applicable security approach while protecting user privacy. We make CGA more privacy-conscious by changing addresses over time which protects users from being tracked. We propose to reduce the CGA granularity of the security level from 16 to 8. We believe that an 8 granularity is more feasible for use in most applications and scenarios. These extensions to the standard CGA are implemented and evaluated.

Cryptographically Generated Addresses (CGAs): Possible Attacks and Proposed Mitigation Approaches

Cryptographically Generated Addresses (CGAs) were mainly designed to prove address ownership and to prevent the theft of existing IPv6 addresses by binding the owners public key to the generated address. The address owner uses a corresponding private key to prove its ownership by using signed messages that are originated from that address. Though the CGA approach is quite useful in providing a means of proving address ownership in IPv6 networks, it does have some limitations and some vulnerabilities. In this paper we will provide a security analysis and descriptions of possible ways of attacking CGA. We found that the CGA verification process is prone mainly to Denial-of-Service (DoS) attacks. We also found that CGAs are still susceptible to privacy related attacks. We will therefore propose some extensions to the CGA standard verification algorithm to mitigate DoS attacks and to make CGA more privacy-conscious.

CS-CGA: Compact and more Secure CGA

Cryptographically Generated Address (CGA) is one of the most novel security features introduced in IPv6 suite. CGA is designed to prevent addresses theft without relying on trust authority or additional security infrastructures. However, CGA is relatively computationally intensive, and bandwidth consuming. Besides, it has some security limitations. This paper defines a Compact and more Secure CGA (CS-CGA) version. We adopt Elliptic Curve Cryptograph (ECC) keys in CGA instead of standardized RSA keys in order to minimize the size of CGA parameters and reduce CGA generation time. To enhance the security of CGA against the global time-memory trade-off attack, the subnet prefix is included in Hash2 calculations of CGA generation algorithm. For the signature and the key calculations, SHA-256 is used instead of SHA-1, which is known to have security flaws.

A-RSA: Augmented RSA

Today, RSA algorithm is the most widely used public-key cryptosystem around the world. It is used for security in everything from online shopping to cell phones. However, the basic RSA is not semantically secure, i.e., encrypting the same message more than once always gives the same ciphertext. For this reason, the basic RSA is vulnerable to set of indirect attacks, such as known plaintext, chosen plaintext, timing, common modulus, and frequency of blocks (FOB) attacks. Moreover, RSA is known to be much slower than the standards symmetric key encryption and it does not used for encrypting large data. In this paper, we design and implement a swift and secure variant of RSA based on Rabin and Huffman coding called Augmented RSA (A-RSA) to solve aforementioned limitations of the basic RSA. A new additional randomization component r is added in A-RSA. This component is encrypted by Rabin algorithm to improve the security level of RSA against the indirect attacks and make RSA semantically secure. Moreover, A-RSA makes the factorization problem harder, since the attackers need to break the factorization of large numbers for both RSA and Rabin. Besides, employing Huffman Coding compression in A-RSA prevents FOB attack and speeds up the execution time for the A-RSA. Our testing results over set of file sizes of 1MB, 2MB, 3MB, to 10 MB show that A-RSAs average execution time is equal to 0.55 of the average execution time of the basic RSA in encryption process and 0.01 in decryption process. Also, we found that RSA system increases the size of ciphertext by 1% compared to the original file size, while the average size of A-RSA files is equal 0.46 of its original sizes.

CGA integration into IPsec/IKEv2 authentication

In IPv6 networks, two security mechanisms are available at the network-layer; SEcure Neighbor Discovery (SEND) and IP security (IPsec). Although both provide authentication, neither subsumes the other; both SEND and IPsec mechanisms should be deployed together to protect IPv6 networks. However, when a node uses both SEND and IPsec, the authentication has to be done twice, which increases the burden on the node and decreases its performance. In this paper, we propose an approach to enable them to work together under the mediation of an Authentication Management Block, where IPsec uses the public-private keys obtained by SEND rather than negotiating its own authentication credentials in order to save the time and facilitate the IPsec authentication deployment. We implement and evaluate our approach using ipsec-tools and DoCoMo SEND implementations. Our proof-of-concept experiment shows a considerable speedup of IPsec authentication time.

IPv4/IPv6 Handoff on Lock-Keeper for High Flexibility and Security

In response to the emerging deployment of IPv6 on network devices, this paper proposes the integration of IPv6 on Lock-Keeper, an implementation of a high level security system for preventing online attacks. It is designed to permit the secure data exchange over physically separated networks in an IPv4-based environment. A new intercommunication module is added to manage IPv4/IPv6 handoff inside the Lock-Keeper, which provides several benefits. First, the Lock-Keeper gains the flexibility to work in IPv4/IPv6 environments. Second, an application layer gateway to bridge IPv4 and IPv6 networks is achieved. Third, the IP-layer protocol isolation is realized inside the Lock-Keeper to enhance the security of the protected network by exchanging data between physically separated networks using different IP protocols.