Fast reduction is a powerful modular reduction method for many ECC curves using NIST-style prime modulus. Based on fast reduction, existing vectorized modular multiplication schemes (such as MR and SMCOS) were constructed in succession. However, these schemes are only applicable to those NIST-style primes with just subtraction items. The vector design on fast reduction for ones with addition items (including certain well-known curves, NIST P-256 and SM2, etc.) rarely holds in practice because of the possible borrow situation. In this work, we fill this gap and propose a pipelined and vectorized fast reduction that, with the aid of pre-processing and post-processing, eliminates all potential borrow during the reduction. Based on the proposed reduction, we successfully construct a vectorized modular multiplication, namely Borrowless, which works with all NIST-style primes, including the ones with addition items. Using NIST P-256, SM2, and NIST P-224 curves as case studies, on the 32-bit ARM NEON platform, we demonstrate the effectiveness of Borrowless and its significant performance advantage over existing vector designs (e.g., CICOS and MR) and widely-used algorithm libraries (e.g., OpenSSL and GMP).

Real time streaming data accounts for a growing proportion of Internet traffic. The demand for security is accordingly increasing, which poses severe burdens on the performance of terminal processing streaming data. In this paper, a high performance video encryption scheme (HPVES) is proposed to speed up cryptographic operations for streaming media data based on cryptographic USB key. In our scheme, the cryptographic key is stored and used in USB key, a dedicated hardware security module (HSM), which avoids the leakage of cryptographic key even when the terminal is compromised. We modify the cos (chip operating system) driver of USB key which is then called HPUK to accelerate data transmission between computer and its' peripherals. A flow control mechanism is also proposed to balance the throughput of keystream and media stream which could (1) make data encryption/decryption maintain at a constant throughput in regardless of the data size and (2) save storage space. We have implemented the proposed scheme and evaluated the performance on different devices. The evaluation demonstrates that HPUK almost doubles the throughput of original USB key on resource-constrained devices at small packet size (no more than 1.5 KB, which suits for real-time UDP transmission). Field experiments also show that HPVES could provide continuous and stable keystream with throughput of 4 MBps.

Numerous works have experimentally shown that Intel Software Guard eXtensions (SGX) is vulnerable to side-channel attacks (SCAs) and related threats, including transient execution attacks. These threats compromise the security of SGX-protected apps. Obfuscating data access patterns is a realistic way to guard against these threats. However, existing defenses impose either too much performance overhead or additional usage restrictions (such as multi-threading). Furthermore, these obfuscation schemes may no longer work if the attacker has the capacity to single-step the target application.